<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>前端必会css布局</title>
  </head>
  <style>
    body, ul {
      margin: 0;
      padding: 0;
    }
    ul {
      list-style: none;
    }
    .container {
      width: 1200px;
      height: 1500px;
      margin: 0 auto;
    }
    .column2 {
      border: 1px solid #000;
      margin-bottom: 20px;
    }
    .column2-1 {
      width: 700px;
      height: 300px;
      background-color: brown;
      float: left;
    }
    .column2-2 {
      width: 480px;
      height: 300px;
      background-color: yellow;
      float: right;
    }
    .clear {
      clear: both;
    }
    .column3 {
      border: 1px solid blue;
      margin-bottom: 20px;
    }
    .column3-1 {
      width: 400px;
      height: 300px;
      background-color: brown;
      float: left;
    }
    .column3-2 {
      width: 400px;
      height: 300px;
      margin-left: 20px;
      background-color: yellow;
      float: left;
    }
    .column3-3 {
      width: 360px;
      height: 300px;
      background-color: yellow;
      float: right;
    }
    .clearfix::after {
      content: "";
      display: block;
      clear: both;
    }
    .column-n {
      background-color: #ddd;
    }
    .column-n li {
      width: 230px;
      height: 190px;
      margin: 5px;
      background-color: aquamarine;
      float: left;
    }
  </style>
  <body>
    <div class="container">
      <div class="column2">
        <div class="column2-1"></div>
        <div class="column2-2"></div>
        <div class="clear"></div>
      </div>
      <div class="column3 clearfix">
        <div class="column3-1"></div>
        <div class="column3-2"></div>
        <div class="column3-3"></div>
      </div>
      <div class="column-n">
        <ul class="clearfix">
          <li></li>
          <li></li>
          <li></li>
          <li></li>
          <li></li>
          <li></li>
          <li></li>
          <li></li>
          <li></li>
          <li></li>
        </ul>
      </div>
    </div>
  </body>
</html>
